Philippine Journal of Science
150 (6A): 1351-1377, December 2021
ISSN 0031 – 7683
Date Received: 15 Apr 2021

Genomic Insights into the Antimicrobial and Anticancer
Potential of Streptomyces sp. A1-08 Isolated from Volcanic Soils
of Mount Mayon, Philippines

Kristel Mae P. Oliveros¹*, Albert Remus R. Rosana²*, Andrew D. Montecillo¹,
Rina B. Opulencia¹, Arian J. Jacildo³, Teofila O. Zulaybar^4†,
and Asuncion K. Raymundo¹

¹Microbiology Division, Institute of Biological Sciences
University of the Philippines Los Baños, College, Laguna 4031 Philippines
²Department of Chemistry, University of Alberta
Edmonton, Alberta T6G 2G2 Canada
³Institute of Computer Science, University of the Philippines Los Baños
College, Laguna 4031 Philippines
⁴Antibiotics Laboratory, National Institute of Molecular Biology and Biotechnology
University of the Philippines Los Baños, College, Laguna 4031 Philippines

*Corresponding author:
rosana@ualberta.ca; kpoliveros@up.edu.ph
^†Deceased: 12 Mar 2021

 

ABSTRACT

Antimicrobial resistance (AMR) poses a global and developmental threat to humanity. The rapid emergence and spread of drug-resistant pathogens resulted in the ineffective use of currently available antibiotics. Therefore, there is a need to continue searching for additional sources of antibiotics, such as actinomycetes, which can potentially harbor unique and effective secondary metabolites. Furthermore, it is interesting to consider poorly explored environments like volcanoes, which can be potential sources of drug leads for medically important natural products. This study reports the antimicrobial activity of actinomycetes isolated from volcanic soil samples collected from Mount Mayon, Albay, Philippines. A total of 13 out of 30 morphologically distinct actinomycete isolates showed antagonistic activity against test microorganisms. Isolate A1-08, the focus of the study, exhibited a wide spectrum of antimicrobial activity against Salmonella enterica, Klebsiella pneumoniae, Staphylococcus aureus, methicillin-resistant S. aureus(MRSA), Candida albicans, Aspergillus niger, and Fusarium sp. Moreover, A1-08 was found to have anti-methicillin resistant S. aureus (MIC = 2.50 mg/mL) and anticancer activity against human colorectal cancer (HCT116) cell line (IC50 = 21.54 μg/mL). Whole-genome sequence-based phylogenetic analysis supported a novel species of Streptomyces closely related to S. olivaceus NRRL B-3009. A total of 48 biosynthetic gene clusters (BGCs) were identified that may be responsible for the biosynthesis of known and potentially novel secondary metabolites. This study concludes that Streptomyces sp. A1-08, a potentially novel species, is a good candidate to produce broad-spectrum antibiotics with anti-MRSA and anti-cancer activities and possibly novel secondary bioactive metabolites of medical and pharmaceutical importance.